The present invention relates to a multiple-way operation switch having an operating rod protruding from the front panel, which switch providing electric signals in accordance with direction of tilting the operating rod. An electronic apparatus incorporating the multiple-way operation switch is also included in the invention.
A conventional multiple-way operation switch is described below with reference to FIG. 11, a cross sectional view.
As shown in FIG. 11, a lower case 1 of an octagonal appearance made with an insulating resin is provided at the upper opening with a depression 1A of octagon shape that substantially corresponds to the octagonal appearance, and a first fixed contact point 4 formed of a central fixed contact point 2 and an outer fixed contact point 3 at the bottom. The central fixed contact point 2 and the outer fixed contact point 3 are electrically connected, respectively, with external terminals 2A and 3A projecting from the lower case 1.
A movable contact 5 of round dome shape made of thin conductive metal plate is placed on the outer fixed contact point 3, making direct contact thereon at the bottom of outer edge 5A.
An upper case 6 of octagonal appearance made with an insulating resin, which case couples with the opening of lower case 1, has a round through hole 6A at the center, and is provided on the bottom surface with eight fixed contact points 7A-7H disposed at an equal distance from the center of the through hole 6A with an equal spacing to each other, as shown in a rear view FIG. 12. Each of the respective fixed contact points 7A-7H is electrically led outside of the upper case 6 to terminals 7I-7P.
Referring to FIG. 13 and FIG. 14, a cylindrical member 8 made of an insulating resin is provided with a through hole 9, formed of a round hole 9A in the upper part and an oblong hole 9B in the lower part. In the middle part of the cylindrical member 8, a conductive flange 10 of octagon shape is provided fixed by an insertion molding, which flange shape being slightly smaller than that of the depression 1A of lower case 1. The cylindrical member 8 and the conductive flange 10 constitute a movable contact body 11.
The movable contact body 11 is inserted and engaged at its upper 10 cylindrical portion 8A of the cylindrical member 8 with the through hole 6A of the upper case 6, and pushed upward by a conductive coil spring 12, housed in the lower case 1, with the upper end of the coil spring 12 making direct contact with the bottom surface of the conductive flange 10. Thus the movable contact body 11 is supported to be able to make tilting motion.
Namely, in a normal state as shown in FIG. 11, the movable contact body 11 is being pushed upward by the coil spring 12, and the upper surface of the conductive flange 10 is in contact with the fixed contact points 7A-7H of the upper case 6, maintaining the neutral position.
The contact points 7B-7D, 7F-7H are not shown in FIG. 11.
The bottom end of the conductive coil spring 12 is always in contact with the outer fixed contact point 3; as the result, the contact points 7A-7H are in electrical connection with the outer fixed contact point 3 by way of the conductive flange 10 and the conductive coil spring 12. So, the terminals 7I-7P and the terminal 3A are also in electrical connection.
The terminals 7J-7L, 7N-7P are not shown in FIG. 11.
An operating rod 13 of round rod shape is penetrating through the through hole 9 of the cylindrical member 8 of the movable contact body 11. The operating rod 13 makes contact at the bottom end 13A with the movable contact 5 at the top point 5B.
The operating rod 13 is provided on the outer circumference in the middle portion with an oblong round portion 13B, which is engaged with the oblong hole 9B of the through hole 9 of cylindrical member 8. In this way, the operating rod 13 is supported by the movable contact point body 11 so that it an move up/down for a certain distance, while no revolving is allowed to each other.
A portion of the operating rod 13 protruding out of the upper case 6 is an operating section 13C. In a normal state where there is no operating force exerted, the movable contact body 11 is pushed upward by the coil spring 12 to be in the neutral position; therefore, the operating rod 13 engaged with the through hole 9 is also held at the neutral position.
Now in the following, operation of the above-configured conventional multiple-way operation switch is described.
As already described, in the normal state where there is no operating force exerted to the operating section 13C of the operating rod 13, both the operating rod 13 and the movable contact body 11 are in neutral position, and the upper surface of the conductive flange 10 of the movable contact body 11 is in contact with the fixed contact points 7A-7H provided in the upper case 6.
When an operating force is exerted to the operating section 13C of operating rod 13 in the direction of left, as shown with an arrow mark in FIG. 15, to tilt the operating rod 13 towards the location where fixed contact point 7E is disposed, the operating rod 13 as well as the movable contact body 11 holding it tilt to compress at the left bottom surface of the conductive flange 10 the left portion of the coil spring 12, with the point where the upper surface of the conductive flange 10 at the right, or at a side opposite to the direction indicated with the arrow mark, and the fixed contact point 7A are making contact as the fulcrum point.
In this state, the fixed contact point 7A locating at the place of fulcrum point keeps contact with the conductive flange 10, while the fixed contact point 7E shown in FIG. 15, and the fixed contact points 7B-7D, 7F-7H (not shown) are separated from the conductive flange 10. These fixed contact points 7B 7H are electrically isolated to be in OFF state.
Tilting of operating rod 13 results in lowering of the bottom end 13A, which pushes the top point 5B of movable contact 5 disposed in the lower case 1. The dome shape of the movable contact 5 is reversed, and the outer fixed contact point 3 and the central fixed contact point 2 are electrically connected by the movable contact 5.
In the above state, the terminal 7I of fixed contact point 7A, the terminal 3A of outer fixed contact point 3 and the terminal 2A of central contact point 2 are electrically connected, while other terminals 7J-7P stay in OFF state.
When the operating rod 13 is tilted to other directions, namely to the directions of respective fixed contact points 7A-7D, 7F-7H, the switch operates in almost the same manner as described in the above. A short description of the operation in such cases is given below.
The movable contact body 11 tilts around a fulcrum point at which one of the fixed contact points 7B-7H disposed in a location opposite to the tilting direction of the operating rod 13 makes contact with the conductive flange 10, only one fixed contact point locating at the fulcrum point among those fixed contact points 7B-7H remains in electrical conduction while the other contact points leave to OFF state. The movable contact 5 is pushed as a result of lowering of the operating rod 13 caused by the tilting operation, and the dome shape is reversed, bringing the outer fixed contact point 3 and the central fixed contact point 2 into electrical conduction via movable contact 5. The state of electrical connection among the fixed contact points 7A-7H, the central fixed contact point 2 and the outer fixed contact point 3 are delivered outside through respective terminals 7I-7P, 2A and 3A.
As soon as the tilting force exerted on the operating rod 13 is withdrawn, the coil spring 12 and the movable contact 5 are restored respectively to the initial shape, the elastic restorative force of these items pushes the movable contact body 11 and the operating rod 13 upward setting them to the normal stand as shown FIG. 11.
In other case when the operating section 13C of operation rod 13 is pushed vertically down while it is in the normal state as shown in FIG. 11, only the operating rod 13, which is coupled with the cylindrical member 8 through the through hole 9 so that it can slide up and down, moves down to push at the bottom end 13A the top point 5B of movable contact 5. The movable contact 5 is reversed in the shape, while the movable contact body 11 is maintained at the normal position being supported by the upward pushing force of the coil spring 12. The reversed movable contact 5 brings the outer fixed contact point 3 and the central contact point 2 into electrical contact. This state is shown in FIG. 16.
In the above described state, where the outer fixed contact point 3 and the central fixed contact point 2 have been brought to ON state by the pressing operation, the fixed contact points 7A-7H, which are electrically connected with the outer fixed contact point 3 via the conductive flange 10 and the coil spring 12, are connected also with the central fixed contact point 2. Thus, all of the terminals 7I-7P, 2A and 3A are in electrical connection.
As soon as the pushing force given on the operating rod 13 is withdrawn, the movable contact 5 is restored to the initial dome shape, the restorative force of which pushes the operating rod 13 up to the normal stand as shown FIG. 11.
However, the above-described conventional multiple-way operation switch, which comprises an upper switching portion formed of the fixed contact points 7A-7H and the conductive flange 10 and a lower switching portion formed of the movable contact 5, the outer fixed contact point 3 and the central fixed contact point 2, and can change the state of contact in both the upper switching portion and the lower switching portion by a certain specific operating action exerted on the operating rod 13, harbors certain drawbacks. With respect to the upper switching portion, among others, when the operating rod 13 is accidentally tilted even for a slightest amount it easily separates the conductive flange 10 from the fixed contact points 7A-7H, bringing either one of the fixed contact points 7A-7H into OFF state. In the conventional multiple-way operation switch, the state of contact can be changed in the upper switching portion and in the lower switching portion by a tilting action of the operating rod 13; however, there is other drawback that since the switching in the upper switching portion and the lower switching portion take place almost at the same timing scope of application is limited. Namely, the conventional switch can not be used in such applications where two kinds of switch signals generated with a certain time lag are needed; for example, a case where a selection signal is needed for selecting a desired menu among a number of menus and then another signal is needed for fixing and entering the selected menu.
The present invention addresses these drawbacks with the conventional multiple-way operation switches, and aims to offer a multiple-way operation switch provided with superior operational functions, with which switch the state of upper switch portion dose not easily shift even if operating rod is slightly tilted by a careless action of an operator, state of contact in the upper switching portion alone can be changed by manipulating the operating rod within a certain specific small angle, and by tilting the operating rod a step further the state of contact in the lower switching portion is changed keeping the state of the upper switching portion as it is.
A multiple-way operation switch of the present invention comprises a lower case provided at the recessed bottom with a lower switching portion formed of a first fixed contact point and a movable contact making on/off contact with the fixed contact point, an operating rod supported at the center of the upper opening of the lower case so that it can slide up and down for pushing down the movable contact of the lower switching portion, and a movable contact body provided with a conductive flange at the outer periphery, which flange being held with immediate contact on a holding member which is pushed upward by pressing force of a press member provided in the lower case while an upper spherical portion of the movable contact body is pressed upward by the pressing force to be coupled with a spherical wall of an upper case so that the movable contact body can tilt. When the movable contact body is tilted as a result of tilting operation exerted to the operating rod, the flange of movable contact body makes contact in part with at least two of a plurality of second contact points provided on the reverse surface of the upper case; this constitute an upper switching portion.
The above-configured multiple-way operation switch offers superior operational functions. When the operating rod is tilted for a certain specific angle, part of the conductive flange of movable contact body makes contact with certain specific contact points among the second fixed contact points disposed in the upper case; thus the state of contact at the upper switching portion is changed while the state of lower switching portion is kept unchanged. When the operating rod is tilted further for a greater angle, the movable contact body tilts a step more with the point of contact as the fulcrum, and the lowering bottom end of the operating rod pushes the lower switching portion down to change the state of connection.